title: "Week 1: Resuscitation"
Week 1: Resuscitation
1. The ABCDE Approach & Deteriorating Patient
The DETECT System
The DETECT approach provides a systematic method for assessing deteriorating patients:
| Letter | Assessment |
|---|---|
| D | Danger (personal safety first) |
| E | End of bed assessment |
| T | Talk to the patient |
| E | Examine systematically |
| C | Call for help |
| T | Treatment/Transfer |
ABCDE Assessment
Systematic approach to the deteriorating patient
ABCDE approach: treat life-threatening problems as you find them — do not complete the full assessment before intervening. If the airway is compromised, secure it before moving
ABCDEFG Systematic Assessment
| System | Look/Listen/Feel | Key Observations |
|---|---|---|
| A - Airway | Stridor, gurgling, snoring | Patent? Obstructed? Partial? |
| B - Breathing | RR (Respiratory Rate), SpO2 (Peripheral Oxygen Saturation), chest movement, breath sounds | Tachypnoea? Hypoxia? Work of breathing? |
| C - Circulation | HR (Heart Rate), BP (Blood Pressure), CRT (Capillary Refill Time), colour, urine output | Tachycardia? Hypotension? Cool peripheries? |
| D - Disability | GCS (Glasgow Coma Scale), pupils, BSL (Blood Sugar Level) | Altered consciousness? Hypoglycaemia? |
| E - Exposure | Temperature, rashes, wounds | Fever? Hypothermia? Source? |
| F - Fluids | Fluid balance, oedema | Hypovolaemia? Overload? |
| G - Glucose | BSL | Under 4 or over 11 mmol/L? |
AVPU - Rapid Consciousness Assessment
- A - Alert: eyes open spontaneously, oriented
- V - Voice: responds to verbal commands, may be confused
- P - Pain: responds only to painful stimulus
- U - Unresponsive: no response to any stimulus
AVPU vs GCS: AVPU is a quick screening tool. If the patient is not Alert, calculate full GCS.
- A ≈ GCS 15
- V ≈ GCS 13
- P ≈ GCS 8
- U ≈ GCS 3
- Emergency presentations (undifferentiated illness)
- Elderly patients (reduced reserve, atypical signs)
- Existing comorbidities (less physiological reserve)
- Extreme illness severity (near decompensation)
- Emerging from anaesthesia (residual drug effects)
- Exsanguinating patients (major haemorrhage)
- Exiting critical care units (step-down risk)
These patients need closer monitoring and lower thresholds for escalation.
ISBAR Handover Framework
| Letter | Component | Example |
|---|---|---|
| I | Introduction | "I'm Ian, the medical student looking after..." |
| S | Situation | "I'm calling about Mrs Smith who has become hypotensive" |
| B | Background | "She's day 2 post-op cholecystectomy, PMHx of HTN, DM" |
| A | Assessment | "BP 85/50, HR 110, looks pale, I think she may be bleeding" |
| R | Recommendation | "I think she needs urgent review and consideration for return to theatre" |
ISBAR Handover
Structured clinical communication framework
2. Basic Life Support (BLS)
The DRSABCD Algorithm
| Step | Action | Details |
|---|---|---|
| D | Danger | Check for hazards (syringes, electricity, spills) |
| R | Response | Shout "Are you okay?" + shoulder squeeze |
| S | Send for help | Press emergency button, call 000/MET call |
| A | Airway | Head tilt, chin lift (unless C-spine) |
| B | Breathing | Look, listen, feel for 10 seconds |
| C | CPR | If not breathing normally, start compressions |
| D | Defibrillation | Attach AED/pads as soon as available |
DRSABCD (Basic Life Support)
First 60 seconds of cardiac arrest response
CPR: The Critical Numbers
| Parameter | Target | Evidence |
|---|---|---|
| Compression depth | 5 cm (at least 1/3 chest depth) | Stiell et al., 2014 |
| Compression rate | 100-120/min | ARC Guidelines |
| Compression:ventilation ratio | 30:2 | ARC Guidelines |
| Swap compressors | Every 2 minutes | Prevents fatigue |
| Chest recoil | Complete | Allow full recoil between compressions |
Each minute without defibrillation reduces survival by 10% - this is why minimising interruptions to CPR is critical.
Airway Management
- Head tilt chin lift: Primary technique (avoid if C-spine suspected)
- Jaw thrust: Use if C-spine injury possible
- Intubation NOT shown to improve outcomes in cardiac arrest
- Bag valve mask or LMA (Laryngeal Mask Airway) adequate in first instance
Warning: Avoid over-ventilation! Increases thoracic pressure, decreases venous return, and reduces chance of ROSC.
Two-Hand Bag Valve Mask Technique
- Use C and E grip on mandible
- Provide jaw thrust
- Leave pillow behind head
- Second person squeezes bag
3. Advanced Life Support (ALS)
Shockable vs Non-Shockable Rhythms
| Shockable | Non-Shockable |
|---|---|
| Ventricular Fibrillation (VF (Ventricular Fibrillation)) | Asystole |
| Pulseless Ventricular Tachycardia (pVT (Ventricular Tachycardia)) | Pulseless Electrical Activity (PEA (Pulseless Electrical Activity)) |
How to Identify:
- VF (Ventricular Fibrillation)/pVT (Ventricular Tachycardia): "Wide and fast" or "wide and weird"
- Asystole: Flat line - terrible prognosis
- PEA (Pulseless Electrical Activity): Organised rhythm but NO pulse - think profound hypotension
The COACHED Defibrillation Script
| Letter | Action |
|---|---|
| C | Continue compressions |
| O | Oxygen away (from chest) |
| A | All else clear |
| C | Charging |
| H | Hands off - check rhythm |
| E | Evaluate rhythm (shock or no shock) |
| D | Defibrillate (if shockable) then immediately resume CPR |
Drug Timing in ALS
| Drug | Dose | Timing |
|---|---|---|
| Adrenaline (Shockable) | 1 mg IV | After 2nd shock, then every 2nd loop (4 min) |
| Adrenaline (Non-Shockable) | 1 mg IV | Immediately, then every 2nd loop (4 min) |
| Amiodarone | 300 mg IV | After 3rd shock (shockable rhythms only) |
| Amiodarone (repeat) | 150 mg IV | After 5th shock if refractory VF |
In shockable rhythms, give adrenaline 1 mg IV after the 2nd shock, then every 4 minutes (every second loop).
In non-shockable rhythms, give adrenaline 1 mg IV immediately, then every 4 minutes.
Give amiodarone 300 mg IV after the 3rd shock, then 150 mg IV after the 5th shock if refractory VF/pVT.
Reversible Causes: 4 H's and 4 T's
| 4 H's | Management | 4 T's | Management |
|---|---|---|---|
| Hypoxia | Ventilate with 100% O2 | Tension Pneumothorax | Needle decompression |
| Hypovolaemia | IV fluids, blood products | Tamponade (cardiac) | Pericardiocentesis |
| Hyper/hypokalaemia | Check VBG, correct K+ | Thrombosis (PE/MI) | Thrombolysis/PCI |
| Hypothermia | Active warming | Toxins | Specific antidotes |
PEA (Pulseless Electrical Activity) - Think Causes of Profound Hypotension
- Septic shock
- Massive MI (Myocardial Infarction)
- Bleeding/trauma
- Poisoning
- Obstruction: Tension Pneumothorax, tamponade, massive PE (Pulmonary Embolism)
Traumatic PEA requires volume resuscitation, not standard ALS
The heart is often structurally fine but has nothing to pump. Standard ACLS fails because adrenaline vasoconstricts an empty tank. Save these patients with massive transfusion, bleeding control, and relieving obstructions (tamponade, tension pneumothorax).
Practice the ALS algorithm with real-time drug timing, 2-minute CPR cycles, and training scenarios.
4. Pharmacology in Critical Care
High Risk Medications: A PINCH
| Letter | Category | Examples | Key Concerns |
|---|---|---|---|
| A | Anti-infectives | Gentamicin, Vancomycin | Ototoxicity, Nephrotoxicity |
| P | Potassium/Electrolytes | KCl, NaCl, MgSO4 | Cardiac arrest if wrong dose |
| I | Insulin | All formulations | Hypoglycaemia, variable absorption |
| N | Narcotics/Sedatives | Morphine, Fentanyl, Midazolam | Respiratory depression |
| C | Chemotherapy | Various | Narrow therapeutic window |
| H | Heparin/Anticoagulants | UFH, Enoxaparin, Warfarin | Bleeding |
Pharmacokinetic Changes in Critical Illness
| Phase | Change | Clinical Implication |
|---|---|---|
| Absorption | Delayed/impaired GI absorption | Unpredictable oral drug levels, consider IV (Intravenous) |
| Distribution | Increased Vd (fluid overload), decreased protein binding | Increased free drug, may need dose adjustment |
| Metabolism | Decreased hepatic clearance (sepsis, hypothermia) | Prolonged drug effects |
| Elimination | Decreased renal clearance (AKI (Acute Kidney Injury)) | Accumulation, dose reduce renally-cleared drugs |
Patients at Highest Risk
- Renal impairment (AKI (Acute Kidney Injury)/CKD (Chronic Kidney Disease))
- Hepatic impairment
- Elderly
- Obese
- Neonates/children
- Multiple sedating medications
- Substance misuse history
5. Intubation Pharmacology
Induction Agents
| Drug | Dose | Onset | Duration | Key Features |
|---|---|---|---|---|
| Propofol | 1.5-2.5 mg/kg | 15-45 sec | 5-10 min | Hypotension, pain on injection |
| Ketamine | 1-2 mg/kg | 30-60 sec | 10-20 min | Maintains BP (Blood Pressure), bronchodilator, emergence phenomena |
| Thiopentone | 3-5 mg/kg | 15-30 sec | 5-10 min | Hypotension, decreases ICP (Intracranial Pressure) |
| Midazolam | 0.1-0.3 mg/kg | 1-2 min | 15-30 min | Amnestic, respiratory depression |
Ketamine is preferred in [] patients (maintains BP (Blood Pressure)) and [] (bronchodilator).
Ketamine maintains BP (Blood Pressure) by causing sympathetic stimulation via inhibiting catecholamine reuptake, which releases endogenous adrenaline and noradrenaline.
Caution: In catecholamine-depleted patients (maxed-out vasopressors), this mechanism fails → ketamine can cause hypotension.
Ketamine is ideal for asthmatic patients requiring intubation — it causes bronchodilation via direct smooth muscle relaxation and β2-agonist effect from catecholamine release.
Ketamine maintains BP via sympathetic stimulation (catecholamine reuptake inhibition).
Neuromuscular Blocking Agents
| Drug | Type | Dose | Onset | Duration | Key Points |
|---|---|---|---|---|---|
| Suxamethonium | Depolarising | 1-1.5 mg/kg | 30-60 sec | 5-10 min | FASTEST onset, contraindicated in hyperkalaemia, burns, denervation |
| Rocuronium | Non-depolarising | 0.6-1.2 mg/kg | 60-90 sec | 30-60 min | Can be reversed with Sugammadex |
| Vecuronium | Non-depolarising | 0.1 mg/kg | 2-3 min | 30-40 min | Minimal cardiovascular effects |
Suxamethonium Contraindications:
- Hyperkalaemia or risk factors for hyperkalaemia
- Burns over 24 hours old
- Denervation injuries
- MH susceptibility
- Myopathies
Reversal Agents
Sugammadex (2-16 mg/kg) reverses rocuronium/vecuronium by encapsulation (rapid, complete reversal).
Neostigmine (0.05 mg/kg + glycopyrrolate) is an acetylcholinesterase inhibitor; only reverses partial blockade.
Flumazenil (0.2-1 mg) reverses benzodiazepines but can precipitate seizures in dependent patients.
Naloxone (0.4-2 mg) reverses opioids; short half-life → watch for renarcotisation.
| Agent | Reverses | Dose | Mechanism |
|---|---|---|---|
| Sugammadex | Rocuronium, Vecuronium | 2-16 mg/kg | Encapsulates aminosteroid NMBAs |
| Neostigmine | Non-depolarising NMBAs | 0.05 mg/kg (+ glycopyrrolate) | Acetylcholinesterase inhibitor |
| Flumazenil | Benzodiazepines | 0.2-1 mg | Competitive GABA antagonist |
| Naloxone | Opioids | 0.4-2 mg | Competitive opioid antagonist |
6. Practice Questions
What is your NEXT action?
7. ECG (Electrocardiogram) Interpretation
ECG (Electrocardiogram) Technical Basics
At standard paper speed of 25mm/s, a big square is 0.2 seconds and a small square is 0.04 seconds
Standard calibration: 10 mm vertical equals 1 mV
Heart rate calculation: Rate = 300 divided by the number of big boxes between each QRS complex
Alternative rate method: 1500 divided by the number of small boxes between QRS complexes
Rate ladder: 300-150-100-75-60-50 for 1-2-3-4-5-6 big boxes between QRS complexes
For irregular rhythms, count the QRS complexes in 6 seconds (30 big boxes) and multiply by 10
ECG axis: Lead I positive + aVF positive = Normal axis (-30° to +90°). The electrical vector points left and inferiorly — this is the most common finding.
ECG axis: Lead I positive + aVF negative = Left axis deviation (more negative than -30°). Think left anterior fascicular block, inferior MI, or LVH.
ECG axis: Lead I negative + aVF positive = Right axis deviation (more positive than +90°). Think RVH, PE, lateral MI, or left posterior fascicular block.
ECG axis: Lead I negative + aVF negative = Extreme axis deviation ("no man's land"). Think ventricular rhythm, severe RVH, or lead misplacement.
Normal QRS axis is -30 to +90 degrees
Left axis deviation is more negative than -30 degrees
Right axis deviation is more positive than +90 degrees
6-Step Approach to Rhythm Strips
- Is there any electrical activity present?
- What is the ventricular (QRS) rate?
- Is the QRS rhythm regular or irregular?
- Is the QRS width normal or broad?
- Is atrial activity (P waves) present?
- How is atrial activity related to ventricular activity?
Rapid Tachycardia Triage (Narrow vs Wide)
Regular narrow-complex tachycardia is usually SVT or atrial flutter with fixed block
Irregular narrow-complex tachycardia suggests atrial fibrillation or flutter with variable block
Regular wide-complex tachycardia should be treated as VT until proven otherwise
Irregular wide-complex tachycardia suggests AF with aberrancy or pre-excited AF (WPW)
AV dissociation or capture/fusion beats in a wide-complex tachycardia favor ventricular tachycardia
P Waves
P waves represent atrial electrical activity arising from the sino-atrial (SA) node
Sinus rhythm has one P wave before every QRS with a constant PR interval
Sinus P waves are upright in leads I and II and inverted in aVR
Absent P waves - think AF (Atrial Fibrillation) (most common), sinoatrial blocks, junctional rhythms, or ventricular rhythms
A bifid P wave suggests left atrial enlargement
A peaked P wave (P-pulmonale) suggests right atrial hypertrophy; hypokalaemia can mimic this pattern
Atrial flutter produces sawtooth flutter waves best seen in leads II, III, and aVF
Typical atrial flutter rate is about 300 bpm
PR Interval
Normal PR interval is 0.12 to 0.2 seconds, measured from start of P wave to start of QRS complex
1st degree heart block: PR interval greater than 0.2 seconds
Wolf-Parkinson-White syndrome (WPW): PR interval less than 0.12 seconds with a delta wave (slurred upstroke on R wave)
Wenckebach phenomenon (Mobitz Type I): Progressively prolonging PR interval until a QRS is dropped, then the cycle repeats
Mobitz Type II: Constant PR interval with intermittently dropped QRS complexes
3rd degree (Complete) heart block: P waves present but no association with QRS complexes (atria and ventricles beat independently)
PR depression in all leads with PR elevation in aVR suggests pericarditis
QRS Complexes
Normal QRS duration is less than 0.12 seconds (or 3 small boxes)
QRS prolongation may indicate sodium channel blockade or bundle branch block (BBB)
MARROW = Right bundle branch block → M shaped (RSR') pattern in V1, W shaped pattern in V6
WILLIAM = Left bundle branch block → W shaped (QS) pattern in V1, M shaped pattern in V6
In RBBB, lead V1 shows an M-shaped (RSR') pattern — think "M" from M-ARROW. The delayed right ventricular depolarisation creates a second R wave (R prime).
In RBBB, lead V6 shows a W-shaped pattern with a broad terminal S wave (reciprocal of the V1 RSR').
In LBBB, lead V1 shows a W-shaped (QS) pattern — think "W" from W-ILLIAM. The septum depolarises right-to-left (opposite normal), creating a deep QS complex.
In LBBB, lead V6 shows an M-shaped pattern with a broad notched R wave (delayed left ventricular activation).
R Wave Progression
Normal R wave transition occurs around V3 to V4
Poor R wave progression can suggest anterior MI (or lead misplacement)
Q Waves
A pathological Q wave is defined as: width more than 40ms (1mm), OR depth more than 25% of R wave, OR depth more than 2mm
ST Segments
ST elevation/depression is measured from the J point (junction of QRS and ST segment)
Significant ST elevation: In chest leads ≥2mm in 2+ leads; In limb leads ≥1mm
Horizontal or downsloping ST depression in contiguous leads suggests subendocardial ischemia
QT Interval
QT prolongation can lead to Torsades de Pointes (polymorphic VT), causing syncope or sudden death
Quick screen: the QT interval should be less than half the preceding R-R interval (rough check when HR is 60-100)
QTc (Bazett formula) = QT / √RR where QT and RR are measured in seconds
Corrects QT interval for heart rate to identify true QT prolongation.
QTc longer than 500 ms markedly increases torsades risk
Calcium effects on QT interval: Hypocalcaemia [] QT; hypercalcaemia [] QT
Treatment for Torsades de Pointes includes Magnesium, Potassium infusion, and/or overdrive pacing
T Waves
Peaked T waves (tall, narrow, symmetric) are the earliest ECG sign of hyperkalaemia — check K+ urgently. Also consider hyperacute STEMI (asymmetric, broad-based T waves in a territorial distribution).
The most common pathological cause of T wave inversion is myocardial ischaemia.
Clinical pearl: Always consider ACS (Acute Coronary Syndrome) when you see new T wave inversions.
T wave inversion in V1-V4 with right axis deviation suggests pulmonary embolism (RV (Right Ventricle) strain pattern)
Deep T wave inversions in the context of neurological symptoms suggest major stroke (cerebral T waves)
Other Waves
U waves (extra wave after T wave) suggest hypokalaemia
J waves (Osborn waves) suggest hypothermia
Epsilon waves (small terminal deflection in V1-V3) indicate Arrhythmogenic right ventricular cardiomyopathy (ARVC)
ECG MCQs (image-first)
Rhythm Strip Recognition
What is this rhythm?
What is the most likely diagnosis?
8. IV Cannulation
- Consent and explain procedure
- Hand hygiene and apply non-sterile gloves
- Apply tourniquet 10-15cm above insertion site
- Select vein and clean site (2% chlorhexidine, allow to dry)
- Insert cannula at 10-30° angle, bevel up
- Advance until flashback seen in chamber
- Lower angle and advance slightly, then slide cannula off needle
- Release tourniquet, apply pressure proximally, remove needle
- Secure with transparent dressing
- Flush with 5-10mL saline to confirm patency
9. Toxicology
Clinical Approach: RRSI DEAD
- R - Resuscitation (ABCDE, use Ringer's Lactate over NS to avoid worsening acidosis)
- R - Risk assessment (predict clinical course: benign vs severe)
- S - Supportive care (FAST HUGS IN BED Please)
- I - Investigations/monitoring
- D - Decontamination (activated charcoal, whole bowel irrigation)
- E - Enhanced elimination (dialysis, urinary alkalinisation, multi-dose charcoal)
- A - Antidote (if available)
- D - Disposition (ward, ICU, psych review)
Supportive Care: FAST HUGS IN BED Please
- F - Fluids and Feeding
- A - Analgesia, Antiemetics
- S - Sedation, Spontaneous breathing trial
- T - Thromboprophylaxis, Tetanus
- H - Head up 30° (if intubated)
- U - Ulcer prophylaxis
- G - Glucose control
- S - Skin/eye care, Suctioning
- I - Indwelling catheter
- N - Nasogastric tube
- B - Bowel care
- E - Environment (temperature, delirium prevention)
- D - De-escalation (end of life, stop unnecessary treatments)
- P - Psychosocial support
Common Toxidromes
| Toxidrome | Causes | Key Features | Treatment |
|---|---|---|---|
| Opioid | Heroin, fentanyl, morphine | Miosis, respiratory depression, ↓LOC | Naloxone (titrate to RR) |
| Sedative | Benzos, barbiturates, GHB | Sedation, respiratory depression | Supportive (flumazenil rarely) |
| Sympathomimetic | Amphetamines, cocaine, MDMA | Mydriasis, tachycardia, HTN, hyperthermia | Benzos, cooling |
| Anticholinergic | TCAs, antihistamines, atropine | "Mad, bad, red, dry" - confusion, tachycardia, mydriasis, dry skin | Supportive + benzos; consider physostigmine only in selected cases with toxicology advice (Poisons 13 11 26) |
| Cholinergic | Organophosphates, nerve agents | DUMBELLS: diarrhea, urination, miosis, bradycardia, emesis, lacrimation, salivation | Atropine + pralidoxime |
| Serotonergic | SSRIs + MAOIs, tramadol | Clonus (LL > UL), hyperreflexia, hyperthermia | Cyproheptadine, benzos, cooling |
Physostigmine in anticholinergic toxicity is NOT routine
Contraindications:
- TCA toxicity suspected (QRS (QRS Complex) widening)
- Mixed or unknown overdose
Only consider for severe pure anticholinergic delirium with senior/toxicologist advice (Poisons Info 13 11 26).
Opioid triad: Miosis + Respiratory depression + Decreased LOC
Anticholinergic mnemonic: "Mad as a hatter, blind as a bat, dry as a bone, red as a beet, hot as a hare"
Decontamination
| Method | Indication | Contraindication |
|---|---|---|
| Activated charcoal (50g) | Within 2h of IR ingestion, 4h of SR | Acids/alkalis, metals (Fe, Li), alcohols, hydrocarbons |
| Whole bowel irrigation | Massive OD, metals, sustained-release | Bowel obstruction, perforation |
Enhanced Elimination
- P - Phenobarbitol
- L - Lithium
- A - Acidosis (severe)
- S - Salicylates
- M - Metformin
- A - Alcohols (toxic: methanol, ethylene glycol)
- T - Theophylline
- V - Valproic acid
Key Antidotes
| Toxin | Antidote |
|---|---|
| Paracetamol | NAC (N-Acetylcysteine) |
| Opioids | Naloxone |
| Benzodiazepines | Flumazenil (use cautiously) |
| Beta-blockers | High-dose insulin euglycaemic therapy (HIET) |
| Calcium channel blockers | HIET, IV Calcium |
| Digoxin | Digibind (Fab fragments) |
| TCAs | Sodium bicarbonate (for QRS widening) |
| Warfarin | Vitamin K, FFP/PCC |
| Methanol/ethylene glycol | Fomepizole or ethanol |
| Organophosphates | Atropine + pralidoxime |
10. Australasian Triage Scale (ATS)
| Category | Maximum Wait | Description | Example |
|---|---|---|---|
| ATS 1 | Immediate | Life-threatening | Cardiac arrest, airway obstruction |
| ATS 2 | 10 minutes | Imminent life-threatening | Chest pain, severe dyspnoea, major trauma |
| ATS 3 | 30 minutes | Potentially life-threatening | Moderate dyspnoea, persistent vomiting |
| ATS 4 | 60 minutes | Potentially serious | Minor trauma, urinary symptoms |
| ATS 5 | 120 minutes | Less urgent | Review of results, minor complaints |
Performance thresholds: ATS 1 = 100%, ATS 2 = 80%, ATS 3 = 75%, ATS 4 = 70%, ATS 5 = 70%
What is the ATS maximum wait time?
Three Phases of ED Management
| Phase | Timeframe | Focus |
|---|---|---|
| Resuscitation | 0-10 minutes | ABCDE, life-saving interventions |
| Secondary care | 10-60 minutes | History (AMPLE), examination, specific treatment |
| Tertiary care | 1-24 hours | Consult, Continuity, Communicate (3 C's) |
11. Post-Resuscitation Care
Chain of Survival
- Early recognition and call for help
- CPR (do it early; buys time)
- Defibrillation (do it early; definitive for VF/pVT)
- Post-resuscitation care (optimise outcomes)
Definitive treatment for VF/pVT is early defibrillation.
ROSC - What Next?
Evidence of ROSC:
- Sudden increase in end-tidal CO2 (>40 mmHg)
- Arterial waveform on monitor
- Purposeful movement
- Spontaneous breathing
Post-ROSC Care Priorities
| Domain | Target | Action |
|---|---|---|
| Airway | Secure | Consider intubation if GCS (Glasgow Coma Scale) less than 8 |
| Breathing | SpO2 (Peripheral Oxygen Saturation) 94-98%, normocapnia | Avoid hyperoxia (↑ free radicals) and hypocapnia (↓ cerebral perfusion) |
| Circulation | MAP (Mean Arterial Pressure) >65, SBP (Systolic Blood Pressure) >100 | Fluids, vasopressors as needed |
| Disability | Normoglycaemia | Treat seizures, avoid hyperthermia |
| Investigations | 12-lead ECG (Electrocardiogram), CXR (Chest X-Ray) | Identify cause (STEMI (ST-Elevation Myocardial Infarction) → cath lab) |
| Temperature | Temperature control | Actively prevent fever (≤37.5°C) for at least 72h in comatose survivors |
12. Airway Management — Difficult Airway
LEMON Assessment for Difficult Intubation
- Look externally — facial trauma, large tongue, short neck, obesity, beard
- Evaluate 3-3-2 — 3 fingers mouth opening, 3 fingers hyomental distance, 2 fingers thyromental distance
- Mallampati score — Class I–IV; III–IV predict difficult laryngoscopic view
- Obstruction — epiglottitis, abscess, tumour, foreign body
- Neck mobility — C-spine collar, ankylosing spondylitis, rheumatoid arthritis
LEMON is a bedside assessment to predict difficult direct laryngoscopy. Multiple positive features → prepare backup airway plans.
Rapid Sequence Intubation (RSI (Rapid Sequence Intubation))
RSI (Rapid Sequence Intubation) = simultaneous induction agent + neuromuscular blocker after pre-oxygenation, without bag-mask ventilation (to avoid gastric insufflation and aspiration).
| Step | Action | Key Detail |
|---|---|---|
| 1. Preparation | Equipment, drugs, team roles | Check laryngoscope, ETT (+ 1 size up/down), bougie, suction, backup LMA (Laryngeal Mask Airway) |
| 2. Pre-oxygenation | 3 min tidal breathing on NRB or HFNC | Creates O₂ reserve (~8 min apnoea time in healthy adults) |
| 3. Pre-treatment | Consider fentanyl (blunt sympathetic response) | Optional — for raised ICP (Intracranial Pressure) or cardiovascular disease |
| 4. Paralysis + Induction | Induction agent → NMBA immediately after | Ketamine 1–2 mg/kg + rocuronium 1.2 mg/kg (or suxamethonium 1.5 mg/kg) |
| 5. Positioning | Sniffing position (ear to sternal notch alignment) | Ramped position for obese patients |
| 6. Placement | Laryngoscopy → pass ETT through cords | Confirm with ETCO₂ waveform (gold standard) |
| 7. Post-intubation | Secure tube, CXR, ventilator settings | Sedation + analgesia infusion |
Confirm ETT placement with continuous end-tidal CO₂ waveform — auscultation alone is NOT reliable. No waveform = not in trachea until proven otherwise.
Can't Intubate, Can't Oxygenate (CICO (Can't Intubate, Can't Oxygenate))
CICO (Can't Intubate, Can't Oxygenate) is a life-threatening emergency. If you cannot intubate AND cannot oxygenate with BVM or supraglottic device → immediate front-of-neck access (FONA).
The Vortex Approach
The Vortex is a cognitive aid for airway management:
Three upper airway lifelines (max 3 attempts each):
- Face mask ventilation (BVM)
- Supraglottic airway (LMA (Laryngeal Mask Airway))
- Endotracheal tube (ETT via laryngoscopy)
If all three lifelines fail → you are in the green zone (CICO) → immediate FONA.
Front-of-Neck Access (FONA)
| Technique | Method | Key Points |
|---|---|---|
| Scalpel cricothyroidotomy | Stab incision through cricothyroid membrane → bougie → tube | Preferred technique in adults; fastest and most reliable |
| Needle cricothyroidotomy | 14G cannula through cricothyroid membrane → jet ventilation | Temporising only; limited ventilation; risk of barotrauma |
| Surgical tracheostomy | Formal incision below cricoid | Definitive but slow; not for emergencies |
Landmark: Palpate the thyroid cartilage → slide down to the cricothyroid membrane (soft depression between thyroid and cricoid cartilage). This is your FONA target.
13. Altered Mental State
Structured Approach: AEIOU-TIPS
- Alcohol — intoxication, withdrawal
- Epilepsy / Endocrine — post-ictal, status epilepticus, hypoglycaemia, thyroid storm, Addisonian crisis
- Insulin — hypoglycaemia, DKA, HHS
- Opiates / Overdose — drug toxicity, poisoning
- Uraemia — renal failure, hepatic encephalopathy
- Trauma — head injury, raised ICP
- Infection — meningitis, encephalitis, sepsis
- Psychiatric — catatonia, conversion disorder (diagnosis of exclusion)
- Stroke / SAH — ischaemic, haemorrhagic, subarachnoid
Immediate priorities in altered mental state:
- ABCDE — secure airway if GCS less than 8
- Check BSL — treat hypoglycaemia immediately (50 mL of 50% dextrose IV)
- Check pupils — asymmetry suggests structural cause (herniation, stroke)
- Consider naloxone — if pinpoint pupils + respiratory depression
Always check BSL in altered mental state — hypoglycaemia is the most rapidly reversible and dangerous cause to miss.
| Investigation | Looking For |
|---|---|
| BSL (bedside) | Hypoglycaemia (less than 4 mmol/L) |
| ABG/VBG | Metabolic acidosis (DKA, toxic ingestion), hypercapnia |
| FBC, UEC, LFTs, CRP | Infection, renal/hepatic failure, electrolyte disturbance |
| Blood cultures | Sepsis |
| CT brain | Stroke, haemorrhage, raised ICP, mass lesion |
| Lumbar puncture | Meningitis, encephalitis, SAH (if CT negative) |
| Toxicology screen | Drug overdose, poisoning |
| ECG | Arrhythmia, drug toxicity (QTc prolongation) |
Time-critical causes to exclude first: Hypoglycaemia → Meningitis → Stroke. All three have interventions that are time-dependent.
See also: Headache Differentials, Status Epilepticus (Week 7 — Disability)
What is the most important immediate intervention?
Week 1 Study Checklist
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